Oxide ion conductivity and relaxation in CaREZrNbO7 (RE=La, Nd, Sm, Gd, and Y) system

Rare earth elements based oxide ion conductors

“…7). 66 This structure can tolerate vacancies at the A and O sites to a certain extent, which can generate pathways for oxygen transport. Generally, pyrochlores can be divided into two major classes depending on the combination of oxidation states, namely, (2+, 5+) pyrochlores and (3+, 4+) pyrochlores.…”

Influence of processing conditions on the ionic conductivity of holmium zirconate (Ho2Zr2O7)

“…Lanthanide based binary oxides crystallising in pyrochlore structure have received significant attention in recent years due to their diverse applications. Their properties such as semiconducting behaviour [1] , ionic conductivity [2,3] , ferromagnetism [4] , luminescence [5,6] , radiation stability [7,8] have been explored in their respective fields of applications. Oxide pyrochlores found their applications as antireflective/protective coatings and refractory matrices for optical devices, dielectric ceramics for microwave wireless communication devices, nuclear waste-storage materials, catalysts and oxygen conductors in fuel cells [9] .…”

Tunability of structure from ordered to disordered and its impact on ionic conductivity behavior in the Nd2−yHoyZr2O7 (0.0 ≤ y ≤ 2.0) system

“…Among the majority of the known pyrochlore oxides under investigation, the III-IV pyrochlores are the ones in which the A 3+ (larger) and B 4+ (smaller) ions occupy the 16d (1/2, 1/2, 1/2) and 16c (0, 0, 0) positions, respectively. The two crystallographically distinct oxide ions, O (1) and O (2), are present at the 48f (x, 1/8, 1/8) and 8b (3/8, 3/8, 3/8) positions, respectively. The third oxygen position, O(3), which is vacant in this structure, would be required to complete the anion arrangement in a fluorite lattice.…”